Walker Frederick, Leading Telegraphist, J/25725, HM Submarine K4, Royal Navy
31st January 1918
Aged 26 (Actually 21 per Royal Navy Service Records)
Son of Robert and Agnes Walker, of Dale Abbey, Ilkeston, Derbyshire
Commemorated on the Plymouth Naval Memorial, Panel 27

Royal Navy Service Records index held by the National Archives
Born Derby, 6th February 1897

1911 Census
Born Little Eaton, Derbyshire, about 1898
A school boy
Son of Robert, a sand contractor's labourer, and Agnes Walker, of The Moor, Dale Abbey, Derbyshire

HMS K4 was a British K class submarine built by Vickers in Barrow-in-Furness. She was laid down on 28 June 1915 and commissioned on 1 January 1917. K4 was lost on 31 January 1918 during the night time fleet exercises later known as the Battle of May Island (Operation E.C.1) when she was attached to the 13th Submarine flotilla. While attempting to avoid a collision with HMS K3, she became the victim of collisions with HMS K6 and HMS K7. She was lost with all hands. The wreck is designated as a protected place under the Protection of the Military Remains Act 1986.
A top-secret mission in the Firth of Forth in 1918 led to 105 deaths when two K-class submarines were sunk with no shots fired in what is known as the Battle of the Isle of May. A flotilla of nine submarines and a convoy of battleships set sail from Rosyth naval base for a night exercise 13 miles off the Fife coast. The vessels were ordered to maintain radio silence and extinguish navigation lights as they made their way through the heavy mist. Disaster struck when the K22 had to change course to avoid a mine-sweeping trawler. The manoeuvre jammed K22's rudder, sending it into K14, killing two of K14's crew members. HMS Inflexible then hit K22, sheering off the submarine's ballast tank and bending her bows round 90 degrees while HMS Fearless struck K17 and sank the submarine in eight minutes. The escaping crew were mown down by HMS Fearless. Nine crew members survived. Submarine K6 tried to take evasive action and collided with K4, causing K4 to sink with all her crew.